/* -*- Mode: C++; tab-width: 4; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
 *   Copyright 2020-Present Couchbase, Inc.
 *
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 */

#pragma once

#include <couchbase/codec/default_json_transcoder.hxx>
#include <couchbase/result.hxx>

#include <vector>

namespace couchbase
{

/**
 * Represents result of @ref collection#get_any_replica operations, also returned by @ref collection#get_all_replicas.
 *
 * @since 1.0.0
 * @committed
 */
class get_replica_result : public result
{
  public:
    /**
     * @since 1.0.0
     * @internal
     */
    get_replica_result() = default;

    /**
     * Constructs result for get_any_replica operation, or an entry for get_all_replicas operation.
     *
     * @param cas
     * @param is_replica true if the document originates from replica node
     * @param value raw document contents along with flags describing its structure
     *
     * @since 1.0.0
     * @committed
     */
    get_replica_result(couchbase::cas cas, bool is_replica, codec::encoded_value value)
      : result{ cas }
      , is_replica_{ is_replica }
      , value_{ std::move(value) }
    {
    }

    /**
     *
     * @return true if the document came from replica, false for active node.
     *
     * @since 1.0.0
     * @committed
     */
    [[nodiscard]] auto is_replica() const -> bool
    {
        return is_replica_;
    }

    /**
     * Decodes content of the document using given transcoder.
     *
     * @tparam Transcoder type that has static function `decode` that takes codec::encoded_value and returns `Transcoder::document_type`
     * @return decoded document content
     *
     * @par Get flags and value as they are stored in the result
     *  Here is an example of custom transcoder, that just extracts value and flags as they are stored in the result.
     * @snippet test_integration_read_replica.cxx smuggling-transcoder
     *  Usage
     * @snippet test_integration_read_replica.cxx smuggling-transcoder-usage
     *
     * @since 1.0.0
     * @committed
     */
    template<typename Transcoder, std::enable_if_t<codec::is_transcoder_v<Transcoder>, bool> = true>
    [[nodiscard]] auto content_as() const -> typename Transcoder::document_type
    {
        return Transcoder::decode(value_);
    }

    /**
     * Decodes content of the document using given codec.
     *
     * @tparam Document custom type that `Transcoder` returns
     * @tparam Transcoder type that has static function `decode` that takes codec::encoded_value and returns `Document`
     * @return decoded document content
     *
     * @since 1.0.0
     * @committed
     */
    template<typename Document,
             typename Transcoder = codec::default_json_transcoder,
             std::enable_if_t<!codec::is_transcoder_v<Document>, bool> = true,
             std::enable_if_t<codec::is_transcoder_v<Transcoder>, bool> = true>
    [[nodiscard]] auto content_as() const -> Document
    {
        return Transcoder::template decode<Document>(value_);
    }

  private:
    bool is_replica_{ false };
    codec::encoded_value value_{};
};

} // namespace couchbase